Tip22v

Not sure if anyone is still monitoring this thread...

I bought my T35 new from the Turbine Shop (did not know about HAB at the time) about two months ago, everything went pretty smoothly and it arrived about a week after payment. Shortly after I got it I mounted it to my test stand and fired it up. I've never had a propane start turbine so this start process was new to me (I watched every you-tube video I could find on how to start the little T35 prior to my first start). The turbine started right up, I ran it up to full throttle a couple of times and then shut it down with a total run-time of about three minutes. Over the next few weeks I worked on getting the jet ready (Habu32). Last weekend I was finally ready to start the turbine mounted in the jet. I could not get it to ramp beyond beyond the initial propane ignition. After several attempts I disconnected the Kero fuel line to test if the pump was working, it was not. So, I loosened the two screws on front the pump and hooked up a 1.5v battery directly to the pump motor and it started turning. I slowly tightened the screws while the pump motor was turning. I then reconnected the fuel line to the turbine and the pump to the ECU and tried it again, success! The turbine started right up, I ran it up to full throttle a couple of times to make sure everything was working correctly. Next I'll mount the turbine back into the jet and try it again, hoping to get to it this upcoming weekend.
One lesson I learned from this thread that was not obvious in the videos I watched is that you have to be careful not to apply too much propane during the initial ignition sequence. First off, you will get a fairly large fireball, which can't be good inside your jet, and second I'm thinking that if the turbine EGT is too high from the propane the ECU will not start pumping fuel because of the risk of an overtempt? -Tom

tow

First of all, Your pump not running looks a little odd, but could be a result of old fuel (oil) sticking in there as the tolerances in the pump-rotor housing are extremely small. You seem to have solved this apparently. Always a good idea to test the pump manually by applying power directly as long as the pump doesn`t run dry that is. Secondly, on this little gems it`s most important there is absolutely no air in the fuel-system. One air-bubble, and they shut down or will not start! First disconnecty the fuel-line from the turbine, then if you hold the throttle-stick full for a few seconds, the pump will engage and prime the fuel line. Then abort the start, reconnect fuel and you are good to go. As you already have discovered, the starting-gas needs to be applied very carefully. I myself does not even use a valve for the propane.Just opens up the bottle manually and slow, listening for the "pop"of the ignition. As the EGT temp surpasses 100 degree the pump will start. As summary - No Air in the fuel-lines, And filter your fuel, and filter it again! Micro -turbines is much more sensitive than their bigger brothers, but once you get the hang of it it works like a charm! Good Luck!

Tip22v

Henke Torphammar

Somethings are crazy again with RCU, will read and reply more in a bit.....

https://drive.google.com/file/d/1wurOt3hV8eoLloMDx_i2-mIG79hZdCZ-/view?usp=sharing

A vertical video(!) too...

https://www.youtube.com/watch?v=I4W5PpIkGt0

Henke Torphammar

The pump are a delicate thing needing very little voltage in the initial ignition. Sometimes, specially when new it can need a little kick start. If I try to start my engine and it only runs on gas I shut down, cool the engine then just disconnect the JST connector of the pump and make a quick 1sec burst directly from the 2S li-po ECU battery. The connectors mate well if you unplug both ECU+pump. Now the pump gotten the little bump it needed and the turbine will start. This hard core priming will not flood the engine as the solenoid is shut.

The working cycle of a turbine jet is VERY simple. trouble shooting is often fairly easy. Just grab a pen and make a simple chart and like you found your self the problem is often not a big deal to crack.

As with propane I usually run my engine without valve adjusting the flow by hand. Initiating the starts seeing/hearing the engine spin free before adding a little gas, then balancing the flame by sound until the kero is ignited. usually this is a really fast procedure as seen in the video above.

Now over to RCG and drawing some schematics for K30 in a FW L39 :-)

Tip22v

Thanks all for the help, much appreciated.

Tip22v

Went to start my T35 this past weekend and I'm not getting any ignition. I can hear the propane swishing through the engine, but no fire. If the glow plug is bad, what kind of plug is it? Is it different from what we use in our glow engines? I have not yet done any troubleshooting e.g. checking the voltage from the ECU, or removing the plug to check to see if it glows yet. On the Xicoy ECUs I seem to remember that it would tell you if the glow plug was bad, not sure about this ECU. Thoughts?

Thanks,

Tom

scoeroo

My Feedback: (9)

I have the T25 and the plug supplied is a Rossi R1 v.Hot
Hope this helps

Tip22v

Thanks. Have you had any problems with your plug? I've only got about 5 runs on my mine so far. -Tom

Henke Torphammar

Just change plug, no big deal ;-)

Some propane just don't work. If temperature changes up the glow power etc etc....

scoeroo

My Feedback: (9)

No problems so far

Tip22v

Were you able to find these glow plugs here in the US? So far, I've only found them available in Europe...
Can I use any "hot" glow plug e.g. OS #3?

Here is a close-up pic of my glow plug, should the filament be extruded like this? Thanks for the help.

Henke Torphammar

http://www.rcuniverse.com/forum/rc-jets-120/6399770-what-glow-plug-use-turbine-engines.html

Tip22v

Thanks for the link, very helpful

Tip22v

I got my ignition issue worked out. It turns out that the short piece of 3mm tubing that connects the turbine to the little festo fitting was loose, which means that I was pushing propane into the front cavity of the turbine and that could have been bad had it ignited! After I fixed that I experienced the issue with the pump again, so I did want Henke recommended and hit it with brief dose of a 2S lipo, which freed it up. After that it started right up. Question: will the pump issue diminish over time as the pump breaks in?

Some here have mentioned not using the propane electro-valve and just metering the propane manually. I tried that a few times and found that my starts were much less consistent so I will need much more practice to make that viable for me. However, using the propane electro-valve does not mean it has to be installed in the jet. I removed mine from the jet and just hook it externally up for starting, saves a couple of ounces of weight, and my starts are consistent.

Overall I have been very impressed with the T35, it is quite the engineering marvel. This thread has been extremely helpful in working through my issues, big thanks to everyone.

Tip22v

I've got two flights on my T-35 and it's performance has been flawless. I'm running a 710ml tank, according to the Lambert website the T-35 burns 119ml per minute at full throttle, does anyone know what the fuel burn is at idle and half throttle? Thanks, Tom.

Bobneal1

My Feedback: (21)

Anybody using a restriction in the propane line for starting? My T-45 pops most of the time on start and I am trying to eliminate this.

Thanks,

Bob Neal

Bob_B

My Feedback: (11)

Where did you buy your Lambert Motor?

Bobneal1

My Feedback: (21)

http://www.turbinenshop.com/epages/61996464.sf/en_US/?ObjectPath=/Shops/61996464/Categories/Turbinen


Bob Neal

Tip22v

Tip22v

Tip22v

Bobneal1

My Feedback: (21)

Yes I am using the electro valve on the gas. That's a good idea to use a valve to adjust the restriction on the gas! I once had a Merlin 90 that would pop and I put a Robart air restrictor in the gas line drilled to about .030 and it stopped the popping. I got the idea from a Rhino that I had that came with a restriction in the line. I measured the oriface and copied it from that. I will probably try that again. I was just hoping someone might have already figured it out.


Thanks

Tip22v

What would really be nice is a variable electro propane valve controlled by the ecu to automatically ramp up the propane as it ignites (I know, keep dreaming) My T35 is my first propane start turbine so it was fun learning all the nuances of starting it, now that I have my start process repeatable it seems very easy, but I definitely had a few exciting starts while learning

Tip22v

Started up my T35 the other day on the test stand, noticed some fuel dripping out the bottom while it was running. Immediately shut it down. Upon close inspection I found that the festo fitting that screws into the turbine had been damaged in a previous start attempt (had some flames), if you look at the photo the previous fire created an almost perfect little hole in the casing of the festo fitting. I had to remove the starter motor and cowl to find this little hole. The fix was pretty easy, I just replaced the festo fitting, the problem was finding the right festo fitting. I finally found the part at a company in CA, but they would only sell in packs of 10, so I bought 10 If anyone needs one of these let me know, I can hook you up.
After replacing the festo fitting I started it up on the test stand and everything is good to go now.

Here is the hard-learned wisdom I wish to share:
If you have any kind of abnormal start involving flames anywhere except out the exhaust, I highly recommend that you check the propane line tubing as well as the fuel line tubing to make sure they are not damaged in any way. The reason is, if you have any kind of flame during startup it's very possible the propane line will come loose and cause an even bigger fire at your next start, make sure the propane line is secure and snug. You will need to remove the cowl to do this inspection properly. Fortunately, removing the cowl is pretty easy, you just need a very small star bit (not sure of exact size, but its metric and it's small; I bought a Ring door bell and it came with a star bit that works perfectly.)